High soil moisture reduces common scab caused by Streptomyces turgidiscabies and Streptomyces europaeiscabiei in potato

Figures & data

Figure 1. Pre-sprouted seed tubers with different common scab severity used in trials with seed-transmitted inoculum 2012.

From left to right: Visual scores of 10%, 30%, 50% and 0% of surface covered with lesions caused by S. turgidiscabies.

Table 1. Effect of soil moisture on common scab severity (% of tuber surface covered with lesions) in potato tubers at three levels of soil moisture.

	2009		2010		2011
	S. turgidiscabies	S. europaeiscabiei	S. turgidiscabies	S. europaeiscabiei	S. turgidiscabies	S. europaeiscabiei
Moisture
Dry	22.3	11.5	39.0a^a	32.4a	13.2a	17.6
Normal	42.5	6.0	22.0b	25.4ab	9.6ab	17.6
Wet	31.3	5.8	20.0b	11.2b	6.6b	12.0
P-ANOVA	0.401	0.291	0.012	0.03	0.028	0.607

Note: Controlled climate experiments with S. turgidiscabies and S. europaeiscabiei. Average results of four pots per treatment in 2009 and five in 2010 and 2011. Planting and harvest dates: 23 April and 21 July 2009, 6 May and 23 August 2010 and 27 May and 30 August 2011.

^aValues within each entry accompanied by different letters are significantly different according to Tukey's pairwise comparisons at p = 0.05.

Table 2. Effect of seed tuber common scab severity (% of tuber surface covered with lesions) on common scab severity on progeny potato tubers.

Seed tuber	Progeny tuber
S. turgidiscabies
0	0.06
10	1.69
30	1.38
50	0.44
P-ANOVA	0.362
S. europaeiscabiei
0	0.06
10	0.25
30	0.88
50	1.38
P-ANOVA	0.257

Note: Controlled climate experiment with two Streptomyces species. Average results of four pots per treatment. Planted on 19 April and harvested on 11 July 2012.